Silent magnetic switch



Jan. 5, 1954 l. zozULlN ETAL SILENT MAGNETIC SWITCH 2 Sheets-Sheet lFiled OCb. 22, 1951 Jan. 5, 1954 l. ZOZULIN EVAL 2,665,344 SILENTMAGNETIC SWITCH Filed Oct. 22, 1951 2 Sheets-Sheet 2 Patented `an. 5,19544 SILENT MAGNETIC SWITCH Igor Zozulin and Geor British C01 ge J.Okulitch, Vancouver, umbia, Canada Application October 22, 1951, SerialNo. 252,482

Claims priority, application Canada August 13, 1951 (Cl. 20D-67) 3Claims.

This invention relates to electric switches and in particular toelectric switches in which the operation is induced by a permanentmagnet.

In electrical switches and particularly electric switches used tocontrol domestic lighting systems it is the practice to use aconstruction comprising a series or" levers, linkages and toggles toeffect the making and breaking of the circuit. These toggles and leversare moved by the operator from an external point and are held in theirtwo normal positions by means of springs. It was found that this type ofswitch, with its many moving parts experienced great wear at criticalpoints and that after a limited period of use its operation was erraticand undependable. The pivot joints between the levers became worn andallowed an amount of play between the two parts that was sufficient todestroy the positive action of the switch. The springs which urged thecontact points into or out of engagement also lost then` strength aftera short time and the operation of the switch was seriously impaired.

The feature of this invention lies in the use of a permanent magnet asthe urging means in. place of the springs of the old type of switch andinthe method of constructing the switching mechamsm so as to reduce thenumber of parts and thereby7 the number of points of wear. The switchthat 1s the embodiment of the present invention cannot wear out and isvirtually noiseless.

An object of this invention is to provide an electric switch which makesuse of a permanent magnet in place of springs.

A still further object of this invention is to provide an electricswitch which can be hermetically sealed against moisture and dust.

A still further purpose of this invention is to provide an electricswitch, the operation of which is virtually noiseless.

A still further purpose of this invention is to provide an electricswitch which will be actuated by the slightest pressure on a flexibleplastic diaphragm.

A still further object of this invention is to provide an electricswitch which will indicate at a glance whether the switch is in the onor the 01T position.

These and other salient objects of this invention will be apparent fromthe following description and claims when read in conjunction with theappended drawings of which:

Figure 1 is a plan view of the preferred embodiment of the invention.

Figure 2 is a section view through section line A--A of Figure 1.

Figure 3 is a plan view of another embodiment of the invention.

Figure 4. is a section view taken through section line A A of Figure 3.

Referring now to Figures l and 2 it will be seen that the switch is ofstandard size and will t into the conventional Wall box. The outercasing I of the switch is of a dielectric material and is in the form ofa rectangular box, open at one face. Inside the box I at one corner ismounted a permanent magnet 2 held in place by a screw 3 which does notpenetrate through the wall of the box I. The magnet 2 is C-shaped andhas its north and south poles, N and S respectively, facing each otherin spaced relationship. To the left of the magnet 2 is the switchingbeam l: which is made of Bakelite or other dielectric material. The beamd is mounted on a pivot 5 in v such a position as to enable theprojection 5 of beam 4 to lie between the poles of the magnet 2. The endof the projection 6 which is between the poles of the magnet 2 iscomposed of a magnetic metal 1, such as iron to enable it to adhere toone or the other of the poles of the magnet. The beam 4 is provided withan electrical contact point 8 mounted on a projection of the beamextending in the opposite direction from the magnetic projection 6. Thiselectrical Contact point 8 is in abutment with a second electricalContact point 9 when the switch is in the on position. At the top of thedielectric box I, i. e, the open side, there is a diaphragm Il! providedwith two cylindrical protuberances II and I2. rlhe diaphragm I0completely covers the open end of the box I and is secured there in sucha manner as to hermetically seal the switching mechanism againstmoisture and dust. On the beam 4, on the side of the pivot 5 remote fromthe magnet 2 and the contact point 8 are two cylindrical protuberancesI3 and I4 of unequal height, the higher one, I 4 being of a heightsunicient to enable it to touch the diaphragm I5 directly beneath theouter protuberance I2 when the magnetic end I of the beam :i is adheringto the N pole of the magnet 2. When the member 7 is adhering to the Spole of the magnet 2 the beam 4 will have rotated about the pivot 5 tosuch an extent that the lower protuberance 3 has been elevated until ittouches the diaphragm I 0 directly beneath the outer protuberance Il. Inthis position, since the beam 4 has rotated slightly the beam 4 hascaused the metallic end I to move to the neutral position between themagnetic poles. At that moment the contact points 8 and 9 are still inabutment because of the spring adottati action or" the mounting member29. As the lbeam fi is in this position the magnetic end 'l of said beamis haii way between the N and S poles of the magnet 2. At this pointmagnetic attraction is altered and the end l is sharply attracted to theother pole of the magnet to the S pole thus breaking the contactinstantaneously. The contact point S mounted on the beam i by means of ametal projection le which is in turn connected electrically by means ofa flexible conductor 2S to a screw terminal it on the exterior suriaceof the box l.V The screw iii is on the outside oi the box l and isthreaded into a metal plug il which passesI 'through the walls oi thebox i and is sealed therein so as not to disturb the moisture prooiqualities oi the box. The contact point 9 is secured by means or" ametallic spring I8 directly to a metallic plug I, similar to the plugil, the plug i9 also being provided with a screw terminal 20. At eachside of the dielectric box l is a metallic angle bracket 2l and 2S forthe purpose oi securing the switch to a standard wall box 2i .by meansoi screws 22 and 23. A standard push button switch cover plate 2li isplaced over the diaphragm le to complete the assembly and is held inplace by screws 25 and 2t.

When the switch is connected to a circuit the conductors are secured tothe screws it and to. When the metallic end l of the projection 6adheres to the N pole oi the permanent magnet ii the contacts il and 9are touching and the protuberance is touching the diaphragm iii di.-rectly beneath the cylindrical protuberance l2 on the diaphragm it.Since the contacts 3 and 9 are touching the circuit is complete or theswitch is in the on position. When the protuberance iti is pressed ittransmits the pressure to the protuberance ifi and pushes it down. rhismotion moves the metallic end i oi" the projection e and it snaps overand adheres to the S pole or the permanent magnet 2 thus moving thecontact 8 away trom Contact 9 thus breaking the circuit. At the sainetime the protuberance it is moved up until it touches the diaphragm itdirectly beneath the protuberance i i. lThe switch is then in the ofiposition. Pressure on the protuberance il will reverse the process.

ln a second embodiment of this invention as illustrated in lligs. 3 and1i shows the mechanism of the switch in closed circuit position (Fig. 4)The mechanism is mounted in a rectangular box lo oi a dielectricmaterial, the box la, being open at its upper face. Following assemblyor the switch parts inside the box la, a flexible diaphragm 2a oitransparent plastic is tted over the open iace of box and hermeticallyclosed so that the switch mechanism is sealed against dust and moisture.A second rectangular box 3a is provi-ded, similar in construction tostandard type switches, to house the dielectric box la and to providemounting means for the switch. Brackets da and 5c are pressed intodielectric box lc and screws da and. la are provided to atV tach thedielectric box la to the outer box 3a. A cover plate da provides a irontface for the switch and protects the flexible diaphragm 2a against anypossible damage. Screws 9a and ia are provided to hold the cover plate8a in place. A cylindrical protuberance im is formed integrally onflexible diaphragm 2a, this protuberance ila extending through anopening in the cover plate The components to be mounted insidedielectric box ia, comprise a permanent magnet i205 which is fastened toan end face of dielectric box la by means of fastening screw 53a. Amoving beam lila constructed of a dielectric material is pivotallymounted on shaft ica so that the beam can oscillate about the axis ofshaft ld. rIhe ends oi shaft 15a are sealed into box la. A sleeve ld ismounted on beam Ella to provide bearing surface with shaft 15d and toprevent lateral movement of beam lila. Armature pieces lla and ita of aferromagnetic substance are secured to the end of beam ita adjacent theN and S pole faces, which faces are shown sloping in order to obtainmaximum contact with the armature pieces ila and ita. The other end oibeam iria carries a switch contact ida and electrical means oiconnection are provided between Contact lila and a flexible conductor20a. The other end of conduct-or 26a is attached to outlet contact i cwhich has a screw 22a to which outside circuit connection can be made. Aresilient arm 23a or" conducting material is provided having Contact 2daxed at its end in juxtaposition to Contact 19a and outlet contact withscrew 25o is provided for outside circuit connection at the opposite endof the resilient arm 23a. Attached to beam iria and preferably formedintegrally with it are two curved branch arms having knobs Zia and 23dto engage in the small cavities in member lita. 'i-'lember 29a issubstantially cylindrical in shape except ior the slight flange at its'lower end in which the two cavities are formed. This member :lila isattached by pin :ica to the under side oi protuberance lia, so thatpressure on the protuberance lia unit be transmitted through diaphragmZd and the member Zed to the knobs 2id (or 28d) and hence to actuatebeam idc.

To provide indication for oil or on position o the switch, a curved armi la is shown being a part oi beam iria and when the curved arm is inthe position indicated in dotted lines the end or" the arm will show asa spot on the transparent diaphragm. ri`his spot will disappear with thedownward movement of arm tic indicating that the switch is in closedcircuit position.

The operation oi the switch is very simple as slight finger pressure onprotuberance ila causes deflection or"v the diaphragm 2a which in turncauses member 29a to press downwards on the knob 2id and thereby iorces,armature ila to break contact with the N pole of magnet |20.. As theswitching beam ida is pressed downwards the magnetic end lla moves tothe neutral position between the N and S poles oi the magnet. Contactpoints ld and 2da are still in'abutment because of the spring action ofthe mounting member 23a but the attraction ci' the S pole becomes greatenough at this point to cause end ila or beam ido' to snap over sharplybreaking the Contact instantaneously. Armature ld is then contracted bytheS pole of magnet its which holds the switch in open position. Toclose the switch a very slight pressure again on protuberance ilarepeats the above operation with the direrence that the pressure is nowtransferred to Knob 28a causing the armature lg3d to break away from theS pole or magnet 52a and the attraction of the N pole results in theswitch being again placed in closed circuit position.

We claim:

l. An electric switch hermetically sealed within an insulating box openat one side, by a iiexible diaphragm, a per ianent magnet having a northpole and a south pole facing each other across a gap, a beam carrying anarmature at one end and an electrical Contact at the opposite end wwwpivotally mounted within said casing, the said armature extending intothe gap between the said north and south poles, said electric Contact onsaid beam making contact with an electric oontact on the wall of saidbox when said armature adheres to said north pole and said Contact onsaid beam separating from said Contact on said box when said armatureadheres to said south pole, a protuberance on said diaphragm comprisinga button, a pressure and motion transmitting member on the side of thediaphragm remote from said button and arms on said beam to contact saidpressure transmitting member.

2. An electric switch as claimed in claim 1 in which the said arms onsaid beam are separated by the said pivot and only one arm contacts saidpressure and motion transmitting member at a time.

3. An electric switch as claimed in claim 1 in which said exiblediaphragm is capable of distortion in a direction at right angles to itsplane a distance equal to slightly more than one half the distancebetween the said north pole and the said south pole of the said magnet.

IGOR ZOZULIN. GEORGE J. OKULITCH.

References Cited in the le 0f this patent UNITED STATES PATENTS NumberName Date 1,701,357 Butler Feb. 5, 1929 2,267,602 Claytor Dec. 23, 19412,302,250 Penn Nov. 17, 1942

